1. Field of the Disclosure
The present disclosure relates to a noise-reducing circuit, and more particularly to a circuit for reducing EMI (Electromagnetic Interference) noise for use in a power unit of a driver IC (Integrated Circuit).
2. Discussion of the Related Art
EMI noise refers to a noise that generates a problem caused by interference when an electromagnetic (EM) wave created in one electrical circuit, component or part is transferred to another electrical circuit, component or part.
As the operating frequencies of electric products become higher, electromagnetic interference (EMI) has been perceived as a chronic noise problem. Particularly, the operating frequencies of electronic products have reached a few ten megahertz (MHz), or even a few gigahertz (GHz), making the EMI problems more troublesome and serious. Subsequently, an object of finding a solution to the problems is desperately needed.
FIG. 1 is a circuit diagram illustrating a power unit for supplying a power to a driver IC according to prior art and an output unit thereof.
Referring to FIG. 1, a power unit (10) for supplying a power to a driver IC (30) is configured in such a manner that capacitors C1 to C4 for decoupling are connectively interposed between a power input unit (11) and a ground GND. The capacitors C1 to C4 for decoupling are to charge or discharge low frequency or high frequency AC (Alternating Current) components of a current supplied from the power input unit (11).
An output terminal of the driver IC (30) is ‘A’ in FIG. 1, and a signal inputted from the power unit (10) is outputted to the output terminal A through the driver IC (30).
However, the driver IC (30) thus configured is problematic in that EMI noise such as PWM (Pulse Width Modulation) noise or low frequency noise due to capacitor capacity is inputted to the output terminal A.